A01 chaf6542 06 se fm indd

Usability/ user- 

 testing

Representative users 

are observed performing 

representative tasks using 

a system.

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Part 3  Implementation

Jakob Nielsen explains the imperative for usability best in his ‘Usability 101’ (

www.useit.

com/alertbox/20030825.html

 – now unavailable). He says:

On the Web, usability is a necessary condition for survival. If a website is difficult to use, 

people leave. If the homepage fails to clearly state what a company offers and what users 

can do on the site, people leave. If users get lost on a website, they leave. If a website’s 

information is hard to read or doesn’t answer users’ key questions, they leave. Note a pat-

tern here?

For these reasons, Nielsen suggests that around 10% of a design project budget should be 

spent on usability, but often actual spend is significantly less.